Mining-drill



(No Model.) 4 Sheets-Sheet 1.

W. H. JENKINS. MINING'DRILL.

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W, H. JENKINS.

MINING DRILL.

Patented Jan. 29, 1889.A

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Patented Jan. 29, 1889.`

W. H. JENKINS.

MINING DRILL.

(No Model.)

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(No Model.) 4 sheets-sheen 4.

W. H. JENKINS.

MINING DRILL. i No. 396,875. Patented Jan. 29, 1889.

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3*( IW//////% Y am W Sib ire rares V.artnr rricrn TILL/XM ll. JENKINS, OF PHILADELPHIA, PENNSYLVANIA.

SPECIFICATION forming part of Letters Patent No. 396,875, dated January 29, 1889.

Application filed August 22, 1888.

To all whom it may concern:

Be it known that I, 'WILLIAM H. JENKINs, residing in Philadelphia, in the county of Philadelphia and State of Pennsylvania, have invented certain new and useful Improvements in Mining- Drills, of which the following is a speeication.

My invention relates to mining-drills, and it refers more particularly to a patent for mining-drills granted to me l1`elnuary .(l, 188C, No. 335,591; and it consists in the novel construetion and combinatii'm of parts, as will be hcre inafter fully described in the annexed specilication and particularly pointed out inthe claims, reference being had to the accompanying drawings, in which- Figure l is a side view of my improved drill, showing the drill mechanism in a vertical position. Fig. 2 is a front or face view of the drill-carryin frame, parts bein broken away. Fig. 3 is a top plan view of the same, partsl being broken away. Fig. et a central vertical section taken on line l Figs. 3 and 2. Fig. 5 is a detail view illustrating the drill operating cam. Fig. (5 is a horizontal section on the line 6 6; and Figs. '7, 7, and 7l' are detail views of the connecting-disks.

In the accompanying drawings, A denotes a movable frame, in which is nounted the drill-rod B and the drill-operatin g mechanism.

To extensions A A of the frame A are secured stationary slideways C C, in which is arranged to travel a cross-head, D, The crosshead D is formed in two sections, C C', which are provided at their lower interior faces each with a seinicireular recess, c c, having' enlarged head portions c c, which recesses enr brace the upper sten1,e,oii` the drill-rod B, which is provided with a head, e, which tits into the portions c c', as shown. The slideways C are 'formed with V-shaped grooves (l in the direction of their length, in which fit to slide therein. V projections 0303, formed on the edges of the erossehead section C. Upon the outer face of: the cross-head D is secured a U-shaped metal frame, F, the arms d4 di of which extend inwardly and embrace the stationary slideways C C, and it is provided with a downwardly-projecting portion, d', as shown. The frame F is bolted to the cross-head by the bolts 'IJ l) and the pin X.

Serial No. 283,458. (No model.)

G denotes the cranleshalft, which is journaled in the frame A, provided upon its outer end with a suitable crank-haiulle, g, and upon its inner end it is connected with a hollow disk, I-l, into which is rigidly fixed the cam I, the specic construction and operation of which will be hereinafter explained.

The angular extensions or arms di di of the frame F are provided with cani-shaped openings .l J, Aformed of the straight innftions j and the inelines P, formed at their diagonal upper and lower edges with semicircular seats jijl. By reference to the drznvings it will be seen that the openings .l .in the arms d* di are arranged in contra positions-L'. e., the incline portion of one extends from the upper front edge of the straight portion j downward to the lower inner edge of the rear straight portion,j, while in the opposite arm the short straight portion j of the opening is at the rear edge'of the arm. and the incline extending from such rear edge toward the front edge. The purpose of such construction -will presently be described.

K K represent two levers, which are centrally pivoted to the fixed ways C C-one on the outer face of each of the said ways C* and have their upper ends extended and provided with roller-bearings which engage the openings in the arms d." dil, their lower ends being extended at lo L', which ends are arranged to automatically operate upon the chuck L, secured to the drill-rod. These levers normally rest with their upper ends in the upper semicircular seats, j", and are held in such positions by stout dat springs Z l. By refereilce to the drawings it will be observed that the said levers are arranged crosswise in relation to each other, and that the spring' Z presses against the lower extended portion, 7o, of one of the levers and forces the upper end outward, while the spring Z presses against the upper end, 7c', of the opposite lever, and thus throws said end inward.

The drill-rod B is operated by means of the cam and the spring M. The operating-spring M it what is known as a U-spring,7j and it is arranged with its inner leaf, m, between the ends l l of the frame A, which end extends lforward of said ends and rests upon the crosshead before referred to, while its leaf m ex- IOC 5 nut, N, which bears against the leaf my', and

by means of which the tension of said spring may be regulated. The leaf on, as before stated, extends over and presses against the cross-head, and such leaf is applied against a 1o knife-edge center bearing-plate, O, which is secured in recesses o, formed in the upper ends of the cross-head plates C C. By adjusting the leaf m in the manner described the greatest possible range is given to the tensionfriction is reduced to the minimum, and

the altering and changing of the spring are accomplished with ease without otherwise disturbing the machine-a result which could not be accomplished by arranging the operatingzo spring in the manner shown in my previous patent referred to.

The drill-chuck L, which is screwed on the lower end of the drill-rod B, consists of the hub L and the enlarged head L2, provided with a series of radial projections, L, formed 3o chuck L-are so arranged as to 4o same to rotate.

with beveled portions l on their inner edges.

The peculiar construction of the several parts just described-. c., the spring, the cross-head, frame F, the arms K K, and .the accomplish the rotation of the drill in a manner which l will now describe.

In the patent granted to me,.No. 335,591, it will be observed that the drill-rod was operated by the cam and pin, and the spiral spring', and the rotationof the chuck was caused by a cam-arm attached to the cross-head, which operated upon the chuck when it was on its upward movement, and thereby caused the lhis form of device, after some experience, was found to be defective, inasmuch as the proper rotation ot' the chuck was not always accomplished. The chuck was sometimes turned too much, and no positive movement of the same was thereby obtained. By the construction described in the present case the rotation of the drill-chuck iS positively accomplished, inasmuch each blow of the drill-rod operates the chuck a certain degree, and no more or less movement can be communicated to said chuck at each movement of the drill-rod; hence the said rotary movement to the chuck and drill will therefore be always regular.

The rotary movement to the chuck L is accomplished as follows: The chuck being at its lowest position, the cross-head and pin also at that down or under position, power is then applied to crank-shaft, and the cam will be- 6o gin to act upon the pin X and start to raise the cross-head an d the frame F. As the crosshead begins to rise, the chuck will. be lifted to be disengaged from a stop, P, connected to the frame A, (in a manner as will be presently explainech) and before it is entirely disengaged from said stop P the head L will engage with two of its radial projections with the lower ends of the arms K, said arms connecting with said head L at opposite sides of the center of motion of said chucks, as clearly shown in the drawings. A slightly further rise of the cross-head will entirely release the chuck from the stop P. At this time it will be observed that the roller-bearing upper en ds of the arms K will now be at thebegini'ling of the inclines in the openings .l in the said arms d of the frame F, and a still furth er movement ofthe cross-head and the frame F will causethe iuclines to operate the arms and swing them laterally until the rollerbearings reach the scmicircular seats in the lower edges of the openings .l in the arms. The said openings l in the frame and their relation to the operating-crank and pin are such that when the cam drops the pin X the roller-bearing will be at the lowest or inner ends of the openings J, and such movement of the arms K is of a degree sufficient to turn Y the chuck one projection or tooth, the-roller- `bearings of the arms at this time resting against the long straight portions of the openings J will thereby prevent said arms K from further movem ent, an d thus hold the chuck in such rotated position. Now, as the tension of the spring will be immediately applied as soon as the cam drops the pin X, the said cross-head will be so quickly shot forward that the roller-bearin g ends of the arms will tend to bear against the long straight sides of the opening J, and the chuck before it leaves the ends 1 of the arms K will have engaged with the stop l), and the portions k of the arms being then entirely released from contact with the chuck, the tension of the [iat springs Z l will cause the upper ends of said .roller -bcaring ends to again assume their normal positions. 'lhus it will be seen that the chuck, after it has reached its npper movement and has been rotated to the degree described, when the cross -head is acted upon by the spring, and will descend in a perfectly straight line, which is a great desderatum in mining-drills. The stop P, previously referred to, which engages the chuck, is a pivotal one, and consists in pivotin g a bent arm, Q, as at g, to the frame A, its forward end, P, being arranged to project in line of the radial proj ections ou the chuck L, and its opposite arm is formed with an upward ex.- tension, Q, which is provided with a lock, which maybe a bayonet or other similar joint, which connects said arm with a short stud, l, on the :frame A, by means of which the said arm Q mayr be readily disengaged from the stud a and the stop l thrown out of engagement with the chuck, shown in dotted lines, Fig. l. By thus arranging the stop it will be' noticed that the chuck may thereby be turned in either way when it is desired to make any change in the drills, or for other obvious purposes.

Near the lower end of the cross-head I pro vide the drill-rod B with a collar, B', and upon the extensions 5 5 of the frame A, I form a IOO IIO

cushion device, R, which consists of a disk, fl', fitted over the drill-rod B, and vertical circular metal rings, fr', is fitted upon said disk. Placed around the drill-rod B, and arranged to rest between the rings r are a series of circular split rubber rings, By forming the cushion in this manner it will bc seen that the split rubber rings Ir2 may be changed or their number increased or decreased without takin g apart any portion ot' the mechanism, said device forming a cushion against which the rod strikes, and especially protects the jar ot said rod when the drill strikes a seam in the rock.

Upon one side the trame A is provided with a yoke portion, A, which is provided with a longitudinal dovetail opening, A2, into which is fitted a dovetail guide, S, which is integrally form ed with the main i' rame T,which is braced within the mine, and which supports the drillmechanism frame A. The yoke A is also provided with a longitudinal screw -threaded openinfr, A", in which is titted the feed-screw ll, which is passed through the arm T of the frame T and held to said arm by the collars it', and having at its outer end a suitable hand-wheel, t3, by the turning otl which the drill-trame A is ted forward with the drill.

The main supporti11g-frame T consists of the arms T and T2, which are connected with the dovetail guide S, the arm T2 having a pivotal connection upon a bolt connected with a supplemental portion, T", et the frame T, the other arm, T', having a pivotal connection with a U-shaped arm, V, which is connected at its end fn with said arm T and at its opposite end 'n' with the supplemental trame T4 in amanner presently described.

The supplemental trame T1, which is arranged to support the weight of the entire apparatus and to receive the shock, is provided at one end, T5, with an adjustable arm, IV, which is connected to the said end T5 by means oi' the bolt uf, passing' through ears fw of a plate, rc2, and the end T", which plate has fixed thereto the screw-rod w3, upon which the arm 'W adjusted, by means of which the forward end of said frame T"l is securely braced to the sides of the mine. The opposite end ot said frame portion T4 is connected to the column Z and held thereto in such a manner that the saine may have an approximately universal motion in relation thereto. The specitic construction whereby such result is obtained wi ll presently be explained. It will, however, be read ily understood that when said frame is placed in a desired relation to the column the same is securely tixed in such position and the vt'orward end braced by the adj ustable arm IY, the V-shaped arm being also rangement I can at any time swing the main frame, which carries the entire drill mechanism, away from the hole drilled when it is de sired to spoon out the pulverized rock, or when it is necessary to change the drill-bits, or for any other purpose, and when said frame is swungl back the same will again resume its place without the slightest deviation t rom its previous position. To secure said frame T in such position with the supplemental portion T4, and yet provide means ot easily disconnecting the same, I construct it in a manner which I will now j )roceed to describe. The forward end ot the arm T2 is formed with a reduced extension, T", which is of: dovctail form in cross-section, and upon the frame Ti, at its vforward end, I iform a projecting por tion, T7, which tits in the reduced part oi. the arm T2, and is ot' a similar shape in crosssection as the extension T", the two forming a hexagon shape in cross-section when united.

Upon the outer edges ot' the arm Tf" are formed guide-ribs lO, between which tits and slides a U-shapcd bent spring, lil, the i'orward ends, l2, ot' which are termed to snugly tit the outer hexagonal port-ion ot' the .tramearms T2 and T, and thereby hold the same in position together. To secure them in such position, I provide t-he arm T2 with an elongated slot, l, through which and the leaves li li ot' the sjining 1l is passed a bolt-,15, provided with a nut, 1G, by the adjustment of which nut theleaves may be securely held against said arm T2, and thereby hold the parts T2 and T'L t i gether- It', however, the nut is loosened on the bolt, the said leaves will expand, (see Fig. (3,) in which case thev spring and bolt may be moved back, the bolt working in the elongated slot until the front ends ot' the spring will be disengaged from the ends of the arms T2 and T4, and thereby permit the main trame and drill mechanism to be swung on their pivots.

As before stated, the supplemental portion T'l ot the trame T is connected to the column Z in such a manner to t'orm an approximately universal joint, the construction of which is clearly illustrated in Fig. 6 ot` the drawings. By reference to said ligure it will be seen that I form the inner edge ot' the arm 'IJ1 with a disk, lift, which is provided with a series oi' circular V-shaped projections,` 17, which engage with similar V-shaped grooves, 1S, formed in the inner face, l0, of a disk, 20, which is formed Vintegral, with and at the lower end ot the U-shaped arm V, and which disk is also provided on its outer tace with V- shaped grooves il, which engage V-shaped projections on the inner face ot the horizontal portion 22 ot an angle-plate, 23, and through said angle-plate 2S, disks lb' and 20, and the arm T is passed a bolt, 25,'tor1ned with a collar, 2l, entered into a socket, 26, in the arm T1. Said bolt is also provided with a reduced portion, 27, upon which is pivoted the arm T2, as shown. By this arrangement it will be seen that by tightening the nut 28 the disks 16 and 20 will be secured7 and by adjusting the nut 29 the arm T2 also held in position. Upon the vertical portion 30 of the angle-plate V-shaped circular grooves are provided, meshing with similar grooves formed on an angle-plate, 33, said plates 23 and being held in adjustment by means of the bolt 36 and nut 37, as clearly shown in the drawings. The a'ugle-j'ilate 33 is provided with a portion, -i, which extends vertically but at right angles to the part 33, which is provided with V-shaped projections engaging a disk, 38,*having similar grooves, S9, engaging the angle-plate jnojections, said disk 38 beingprovided upon its limer face with lateral ribs 40 l0, between whichis fitted the front end of a connecting-lair, 4l, a nutted bolt, 42, passing through said bar, disk 38, 'and angle-plate, and thus securing said parts together. The connecting-bar ll extends back to and is journaled on the column Z in any well-known manner-,an d'through its extended end 43 is passed an adjustable brace-bar, lei, by means of which and the adj usiable bracearln \V, previously described, the apparatus is securely braced in relation to the 1ninewalls.

From the foregoing it will be seen that by connecting the frame to the column Z in the manner described the frame may have various adjustments. By means of the disk 3l the frame has a movement back and forward in the direction of the length of the connecting-bar, while by means of the disk 23 and its adjustment the frame will have a movement back and forth at right angles to the connecting-Imi, and through the medium of the disk 16 and its adjustments the frame will have a movement back and forth horizontally to the other movements described. This manner of adj Listing the frame, as far as I know, has never been accomplished, and it is found by experience that by such connection every movement of the drill-frame necessary in drilling may be obtained.

By reference to 5 of the drawings the specific construction of the cam I is clearly set forth, and which I will now proceed to describe, previous to which I will refer somewhat to the construction of the cam'device shown in my previous patent, No. 335,591, and thereby point out more particularly wherein my improved construction of cam differs from the same.

In the construction of the cam `in my previous patent it will be seen that at each revolution of the cam the drill-rod is lifted twice, and by arranging the cam portions with their straight faces in dia1netrically-coincident planes that it is necessary to make the pin in a semicircular form to permit it to operate in said cam-faces. In the practical application of the cam described I have :found that when the springtension was of a degree to strike but a moderate blow the revolution of the cam-disk would bring the lower or beginning portion of the cam-groove under the pin before the rod would have reached its lowest point of thrust, and by arranging the camcurve in the manner described it would have its bearing-surface too near the horizontal diameter, thereby decreasing the leverage of the cam upon the pin and greatly increasing' the friction, as the leverage upon said pin was nearer to a sidewise than a vertical pressure. I have found by practical experience that the cam illustrated in Fig. 5 will avoid all of said objections.

rlhe cam I consists of a solid piece of steel securely fitted to the disk H and extending beyond the rim of said disk to a distance of about one-half its thickness. In this plate I forni but a single cam-recess or operatinggroovc, I, the heel or straight portion I2 of which is arranged a short distance to one side of the center of the cam. The beginning or point I3 of the curved portion of said groove commences at a point in the cam-periphery of a distance sufficient to permit of the positive fall of the pin X before said point I3 can turn under it. It will be observed that by extending the straight portion of the cam-groove to one side or the center, of said cam I add distance between the heel and point of said groove without the necessity of increasing the curvature of the curved portion of the groove, and thus avoid additional friction, as each degree of additional curvature to said portion proportionately increases the friction. The curved portion I3 is formed of a compound curve, which rises toward and extends over the center of said cam-face, gradually diminishin g its radial distance from the center, and extending toa distance below said center, and merged into the straight or heel portion, as clearly shown in the drawings. By arranging the cam in this manner it will be observed that but one blow of the drill-rod will be accomplished at each complete revolution of the cam. It will also be readily understood that by the formation of the cam-groove as described, as the pin X continues to rise, the leverage upon said pin will gradually increase, thereby con'lpensating for the addi tional tension upon the spring.

A still further advantage of forming the heel portion to one side of the central line-of the cam is that the pin X can be made of considerably more strength, inasmuch as its straight surface is extended beyond the center and in line with the heel portion, as shown. It will also be observed that by the peculiar formation of the camgroove the curved portion IOO IIO

will lift the pin from its under side and apply its pressure almost in a vertical line, and thereby avoid the side pressure which is encountered in the operation of the cam and pin shown in my previous patent referred to. lhisvertical pressure upon the pin is-continued through the entire lift of the pin while the cam-is being rotated.

From the foregoing description, taken in connection with the drawings, the operation and advantages of my improved drill will be readily understood.

It will be seen that. a -Y drill of great capacity is produced, the mechanism for operating the drill being of such a character as to adapt the same to all classes and conditions of rock, and by the various means of adjustment the same may readily be set for operation at any position desired in drilling.

Having thus described my invention, what l claim, and desire to secure by Letters Patent, 1s-

l. The combination, with a drill-rod having a lifting-pin, of a cam foroperating the same, said cam consisting of a disk provided with groove or cutaway portion l', havinga radial side arranged at one side of the center line of said camdisk, said radial portion ending short of the center of the disk, and a curved side beginning with its point at the opposite side of the said center line, extending from the periphery toward the center, having a gradually-decreasing radius, said curvature extending over and past the center of said cam-disk and ending at the inner end of the radial portion, substantially as and for the purpose described.

2. The combination, with a cam provided with a cam-groove, I, substantially as shown, one edge of which is formed of a radial straight portion arranged to one side of the center of the cam, of a spring-actuated drillrod having a lifting-pin formed with an approximately semicircular bearing face for operation in said groove, and its opposite face formed straight and extended beyond the center of the cam, whereby the pin shall be instantly released by the cam when the said straight portion of the pin and the radial straight side of the groove shall be in coincident planes, substantially as and for the purposes set forth.

3. In a mining-drill, the combination of the drill-supporting frame and the columns Z, for supporting said frame, of a series of adjustable frietion-disks connecting said frame to the column, said disks @insisting of a horizontal disk, 20, adj ustably secured to the drill-supportin frame, provided with a vertical portion, 30, having a central pivot bolt, an angle-plate, adjustably secured upon said plate in frictional contact with the portion 30, said plate provided with vertical portion 34 at right angles to the part 33, a disk, 38, secured upon an arm connected with the column Z, and a pivotal bolt passing centrally through said portion 34 and the disk 38, each of said disk portions having independent adjustments, substantially as shown and described.

at. ln a mining-drill, the combination, with the main frame, a series of adjustable disks formed thereon, as shown and described, and the column Z, of the bar 4l, mounted on the column Z and connected at one en d with the adjustable disks, provided with an extended portion, 43, an adjustable brace-bar, 44, journaled in the portion 43, and the adjustable brace-bar lV, connected to the front end of the main frame, whereby said frame is securely adjusted to the main walls, substantially as shown and described.

5. Ina mining-drill, the combination, with the cam I, journaled in the frame A, fixed guides C C', secured in said frame, provided with Vshaped grooves, the crosshead having V-shaped tongues entered in said grooves, and a lifting-pin connecting said cross-head and cam, of the U-shaped spring resting against plate secured in the upper end of the cross-` head and provided with a knife-bearing edge adapted to supportthe leaf m of the spring M, substantially as and :for the purpose ydescribed. j

7. The combination, with the eross-head D, the drill-rod B, secured thereto, a chuck, L, provided with radial projections secured to said drill-rod, and the cam for operating the drillrod and cross-head, said cross-head formed with cam-recesses in its opposite ends, of the arms K, pivoted to the frame and disposed one to each end of the cross-head D, the upper ends thereof engaging the said cam-recesses, their lower ends engaging the radial projections on the chuck L, said arms adapted to oscillate by the travel of the cross-head, whereby a rotary motion is imparted to the chuck, substantially as and for the purposes shown and described.

8. In a miningdrill, the combination, with the cross-head D, the frame E, secured thereto, having lateral arms (Z4 d4 formed thereon, said arms provided with cam-shaped openings J, arranged in contrarelation to each other, the drill-rod B, connected with the crosshead, and the chuck L, connected to the drillrod, said chuck provided with radial proj ections, of the swin ging arms K, centrally pivoted to the frame A, and disposed one to the outer face of each of the said arms di, connected at their upper ends with the cam-openings J, their lower ends, K, arranged to engage the radial projections on the chuck, said arms adapted to be oscillated by the travel of the cross-head and the cam mechanism for operating the crosshead, substantially as shown and described, as and for the purpose set forth.

9. In a mining-drill, the combination, with the cross-head, the frame F, secured thereto, having arms d4 d4 projecting therefrom over the sides of the crosshead, said arms provided with cam-shaped openings arranged in contrarelation to each other, the drill-rod B, secured to the cross-head, and the chuck L, secured to the drill-rod, provided with radial projections, of the arms K, centrally pivoted upon the sides of the frame, said arms pro- IOO IIO

vided at their upper ends with roller-bearings engaging the cam-openings J in the arms d, their lower ends, 7u, arranged to engage the radial projections, the ehuclcsprings Z Z', for automatically throwing said arms back to their normal positions, and the cam m echanism, substantially as described and shown, for operating the cross-head, all arranged as and i'or the purpose described.

l0. The combination, with. the cross-head carrying the drill-rod, the chuck attached to the said drill-rod, the cam mechanism l, substantially as shown and described, for operating the upward movement of thc crosshead, and the spring vI'oifforcing said crosshead down, of the arms centrally pivoted, said arms arranged to oscillate by contact at their upper ends with cam-faces ot' the cross-head, their lower ends adapted to engage the chuck and revolve the same when said. arms are oscillated, substantially as shown and described.

ll, In a mining-(;lrill,the combination,with the drill-rod and the chuck secured thereto, provided with radial projections, of the pivotal stop l), said stop adapted *to engage the said radial projections, said stop having an extension, Q', provided with a bayonet or other lock joint engaging a stud upon the frame, whereby said stop may be swung out of engagement with said stud and permit ot the rotation of said drill-chuck, substantially as and for the purpose specied.

l2. In a mining-drill, the combination of the main frame provided with a U-shaped arm, 3'

V, forward-extemled arms T and T2, and a supplemental arm, T4, the arms T2 and T4 supporting the drill-frame, said arm T pivoted to the outer end of the -arni V, and the arm T2 pivoted upon the bolt connect-ing said arm V with the arm T4, said connections of arms T T2 permitting the swinging of the frame T and the drill meehan ism away from its working position, substantially as shown and described.

with an elongated slot, of the U -spring embrac- 5 in the arm T2,its forward end adapted to embrace the ends ot' the arms T2 T", and an adjusting-bolt passed through the sjn'ing-arms and the slot, by the adjustment of Awhich the said spring may be slid back and permit the 6 arms T2and T'l to become disconnected,thereby allowing the vFrame to be swungupon its pivo1'ssubstanti all y as shown and described.

wM. n. JENKINS.

ll'itnesses:

FRED G. DiETERieH, SoLoN C. KEMoN. 

